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nanotimes News in Brief

Professor Ravi Silva, Director of the Advanced Technology Institute at Surrey, said: “This research shows the transformational benefits that can happen of bringing high quality specialised experimental facilities to tackle some of the key problems in mo- dern nanotechnology and electronics. The research offers the potential for new applications of carbon nanotubes.”

Ali H. Alshehri, Malgorzata Jakubowska, Marcin Sloma, Michal Horaczek, Diana Rudka, Charles Free and J. Da- vid Carey: Electrical performance of carbon nanotube- polymer composites at frequencies up to 220 GHz, In: Applied Physics Letters, Volume 99(2011), Article 153109 [3 pages], DOI:10.1063/1.3651278: http://dx.doi.org/10.1063/1.3651278

11-10 :: October 2011

European Commission breaks new ground with a common nano definition. The definition adopted is based on an approach considering the size of the constituent particles of a material, rather than ha- zard or risk. The wording describes a nanomaterial as “a natural, incidental or manufactured material containing particles, in an unbound state or as an aggregate or as an agglomerate and where, for 50% or more of the particles in the number size distribu- tion, one or more external dimensions is in the size range 1nm to 100nm.”

http://ec.europa.eu/environment/chemicals/nanotech/ index.htm

Researchers at Northwestern University (U.S.) show in NANO Letters that nanocomposites based on the less defective solvent-exfoliated graphene

exhibit a significantly larger enhancement in CO2 photoreduction, especially under visible light. This counterintuitive result is attributed to their superior electrical mobility, which facilitates the diffusion of photoexcited electrons to reactive sites.

Yu Teng Liang, Baiju K. Vijayan, Kimberly A. Gray and Mark C. Hersam: Minimizing Graphene Defects Enhan- ces Titania Nanocomposite-Based Photocatalytic Red- uction of CO2 for Improved Solar Fuel Production, In: NANO Letters, Vol. 11(2011), Issue 7, July 13, 2011, Pages 2865-2870, DOI:10.1021/nl2012906: http://dx.doi.org/10.1021/nl2012906

University of Constance physicists Daniel Mutter and Peter Nielaba have visualized changes in shape memory materials down to the nanometric scale. Metallic alloys can be stretched or compressed in such a way that they stay deformed once the strain on the material has been released. Only shape memory alloys, however, can return to their original shape after being heated above a specific tempera- ture. For the first time, the authors determine the absolute values of temperatures at which shape memory nanospheres start changing back to their memorised shape – undergoing so-called structural phase transition, which depends on the size of par- ticles studied. To achieve this result, they performed a computer simulation using nanoparticles with diameters between 4 and 17nm made of an alloy of equal proportions of nickel and titanium.